Building-block.



UNITED STATES PATENT OFFICE.

. Specification of Letters Patent.

Patented Feb. 13, 1906.

Application filed March 16, 1905. Serial No. 250,457.

To a, whom it may concern.-

Be it known that I, JOHN A. JoHNsoN, a citizen of the United States,residing at Winamac, in the county of Pulaski and State of Indiana, haveinvented certain new and useful Improvements in Building Blocks, ofwhich the following is a specification.

This invention relates to improvements in concrete building-blocks; andthe object of the invention is to provide a construction of suchmaterial that will absorb and distribute moisture applied to its outersurface in such a manner as to preserve the inner portion of the blockwhich forms the inside wall of the building in a drier condition thanheretofore obtainable.

I accomplish the objects of the invention by the means illustrated inthe accompanying drawings, in which Figure 1 is a top plan view of abuildingblock constructed in accordance with my invention, and Fig. 2 isa vertical section of same on the line 2 2 of Fig. 1.

Like characters of reference indicate like parts throughout both viewsof the drawings.

3 is the front face of the concrete block, here shown as rough inconstruction to represent a rough rock finish. Instead of this rockfinish it may be ornamented in any man: ner to suit the desires of thearchitect or those who are to use the block.

4 represents triangular-shaped openings extending vertically through theblock. One side of these triangular openings is parallel .with the frontface of the block, while the other two sides converge toward the backface of the block. By this construction the openings will be separatedfrom each other by concrete walls or partitions which are wedge-shapedin cross-section, increasing in width toward the back of the block, sothat moisture applied to the outer surface 3 will ered to the back wallin a more concentrated form than in my construction, in which themoisture is not only distributed over the whole inner-face of the innerwall, but the partitions themselves contain a larger amount of concrete,which will take up a proportionately greater amount of said moisture.The result is that a quantity of water which would pass through aconcrete block having rectangular openings and show in well-defineddrops on the inner face of the block would be absorbed before it hadpassed through a block of my construction and the inner face of my blockwould be dry. It will also be noted, as shown in Fig. 1, that I place myventilatingopenings nearest to the front or outer face of the block, soas to make the inside wall of the block thicker than the outside wall.Because of this the columns of air within the air-openings of the blockwill be warmed and dried through the thinner outside wall of the block,and the thicker inside wall will be better protected and rendered moreimpervious to moisture and less sensitive to changes in temperature. Inaddition the greater thickness of the inner wall provides the maximumstrength where it is most needed for the support of joist, girders, andother load-bracing parts of a structure.

Having thus fully described my invention, what I claim as new, and wishto secure by Letters Patent of the United States, is

1. A building-block having vertical airpassages triangular incross-section with a side of each passage parallel with the front faceof the block, said passages being separated by walls which increase inthickness toward the back of the block.

2. A building-block of concrete or other molded material having verticalair-passages separated by walls which increase in thickness toward theback of the block, said airpassages being closer to the front than tothe rear wall of the block.

In witness whereof I have hereunto set my hand and seal, atIndianapolis, Indiana, this 6th day of March, A. D. 1905.

JOHN A. JOHNSON.

